Most microcontroller clock schemes are based on binary dividers of a standard clock. For instance, on conventional microcontroller products if a 16 MHz base clock may be used as the system clock. However, a user may scale down this frequency, in particular for low power applications. Also, peripheral devices may be supplied with clock signals derived from such a system clock by division of 2n, wherein n>1. For example, in the above case the following frequencies may be selected for a system clock or other clock signals derived from the system clock: [8, 4, 2, 1, 0.5, 0.25, 0.03125] MHz. These selectable output frequencies are based on a divider of [2, 4, 8, 16, 32, 64, 512], respectively.